examples/load_lerobot_dataset.py

#!/usr/bin/env python3
"""Load one TacRich-Manip episode and print every key, shape, dtype, and value order."""

from __future__ import annotations

import argparse
from pathlib import Path


def lerobot_dataset_class():
    try:
        from lerobot.datasets.lerobot_dataset import LeRobotDataset
    except ModuleNotFoundError:
        from lerobot.common.datasets.lerobot_dataset import LeRobotDataset
    return LeRobotDataset


def describe(value: object) -> str:
    shape = tuple(getattr(value, "shape", ()))
    dtype = getattr(value, "dtype", type(value).__name__)
    return f"shape={shape}, dtype={dtype}"


def main() -> None:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--repo-id", default="qingzhu-robotics/TacRich-Manip-LeRobot-teleoperation-cyclically-arrange-steel-plate")
    parser.add_argument("--revision", default="main")
    parser.add_argument("--root", type=Path, help="Optional existing local dataset root")
    parser.add_argument("--episode-index", type=int, default=0)
    parser.add_argument("--frame-index", type=int, default=0,
                        help="Zero-based index inside the selected episode")
    parser.add_argument("--video-backend", default="pyav")
    args = parser.parse_args()

    dataset = lerobot_dataset_class()(
        repo_id=args.repo_id,
        root=args.root,
        revision=args.revision,
        episodes=[args.episode_index],
        video_backend=args.video_backend,
    )
    if not 0 <= args.frame_index < len(dataset):
        raise IndexError(f"frame {args.frame_index} outside [0, {len(dataset) - 1}]")
    sample = dataset[args.frame_index]

    print(dataset)
    print(f"selected episode={args.episode_index}, local frame={args.frame_index}")
    print("runtime sample keys:")
    for key in sorted(sample):
        print(f"  {key:48s} {describe(sample[key])}")

    print("\nordered vectors:")
    for key in (
        "observation.state",
        "action",
        "observation.state_gripper",
        "action_gripper",
    ):
        print(f"  {key}: {sample[key]}")

    print("\nCanonical orders are documented in docs/DATASET_SCHEMA.md.")
    print("For exact float64 source times, read the Parquet columns with PyArrow.")


if __name__ == "__main__":
    main()